By way of historical background, hard contact lenses were developed in the late 1940's, gained national prominence in the early 1950's and grew steadily in usage until they have exceeded ten million pairs per year by the 1960's and early 1970's. Since the introduction of the hard contact lens, ophthalmologists and optometrists have taught and used only one method of insertion and removal of hard contact lenses. More specifically, the method of insertion is to place the lens on the end of a finger, such as the index finger, bring the lens to the eye and inserting, while the other hand spreads the eye open. Removal of the hard lens merely requires pulling the outer edge of the upper eyelid taut and blinking rapidly, if necessary. The hard lens would then fall into the user's open palm or onto a towel.
Only ten percent to fifteen percent of those attempting to learn the procedure outlined above failed. And these prospective users were then merely informed that they could not wear contact lenses. Most of the persons failing were older persons whose upper eyelid would not eject the lens, or those whose hands were subject to shaking so that they could not smoothly insert the lenses. All mechanical methods were and are, for the most part, shunned by optometrists and ophthalmologists, since practically all include methods of suction being applied to the contact lens which can severely injure the eye. Typical disclosures showing various suction devices of the type mentioned above include W. Henning, U.S. Pat. No. 3,600,028; R. S. Boone, U.S. Pat. No. 3,791,689; A. Rinaldy, U.S. Pat. No. 2,919,696 and E. H. Carruthers, U.S. Pat. No. 3,934,914.
There was little problem with bacteria in connection with hard contact lenses, and particularly with the insertion and removal thereof, as the hard lenses were not porous, and did not readily pick up bacteria, and the only point of contact with the human hand was between the center of the outside of the hard contact lens and the ball of one finger. As will be developed below, however, the soft contact lens presents a much more serious problem relative to bacteria, particularly with regard to the insertion and removal of these soft lenses.
Soft lenses became nationally known in late 1973. They have come into increasing use since then, and would probably be much more widely used except for the bacteria and infection problems which are particularly pronounced in connection with the insertion and removal of such lenses. More specifically, the soft lens is porous, and requires more finger handling and contact to remove from the case mount and involves much more contact with the fingers as it is much like a thin soaked piece of paper and there is therefore much more opportunity for transferring finger contamination to the eye. Even more serious is the problem of removal since two fingers must be applied to the eye near the opposing edges of the lens, and these two fingers must be moved toward one another so that the lens is squeezed and removed. This is particularly difficult for women who may have long fingernails which may easily contact the eye and scratch its surface. Also, the chance that dirt under fingernails will contact the eye is greatly increased. As a collateral matter, regardless of the care exercised, the soft lenses may be easily damaged by finger handling and must be discarded upon such damage, a matter of several hundred dollars in expense.
As a result of the difficulties in handling soft contact lenses, more than 25% of the normal prospective users are unable to insert and remove such lenses on a regular basis.
It is again noted that the principal approach up to the present time with regard to the insertion and removal of contact lenses has been the suction cup concept. Unfortunately, in order to apply sufficient force to remove contact lenses with a suction cup, sufficiently great force must be applied to the contact lens that the eye may be seriously and permanently damaged. Accordingly, as mentioned above, virtually no ophthalmologists or optometrists recommend any mechanical devices for inserting or removing contact lenses.
A principal object of the present invention is to provide a solution to the foregoing problem, i.e. to provide a non-suction cup-type instrument for the insertion and removal of soft contact lenses which will not damage nor infect the eye.